Non-stick coated electrosurgical instruments and method for manufacturing the same

ABSTRACT

An end effector assembly for use with an electrosurgical instrument is provided. The electrosurgical instrument includes a handle having a shaft that extends therefrom, an end effector disposed at a distal end of the shaft, at least one electrode operably coupled to the end effector and adapted to couple to a source of electrosurgical energy, a titanium nitride coating covering at least a portion of the electrode, a chromium nitride coating covering at least a portion of the electrode and/or titanium nitride coating, and a hexamethyldisiloxane plasma coating covering at least a portion of the chromium nitride coating.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation application of U.S. application Ser.No. 16/598,523, filed on Oct. 10, 2019, which is a continuationapplication of U.S. application Ser. No. 15/332,797, filed on Oct. 24,2016, now U.S. Pat. No. 10,441,349, which is a continuation in partapplication of U.S. application Ser. No. 14/926,553, filed on Oct. 29,2015, now U.S. Pat. No. 10,368,939, the entire contents of which areincorporated by reference herein.

BACKGROUND

The present disclosure relates to an electrosurgical instrument andmethod for sealing tissue. More particularly, the present disclosurerelates to an electrosurgical tool including opposing jaw members havingsealing plates with improved non-stick coatings and methods formanufacturing the same.

Electrosurgical forceps utilize mechanical clamping action along withelectrical energy to effect hemostasis on the clamped tissue. Theforceps (open, laparoscopic or endoscopic) include electrosurgicalsealing plates which apply the electrosurgical energy to the clampedtissue. By controlling the intensity, frequency and duration of theelectrosurgical energy applied through the sealing plates to the tissue,the surgeon can coagulate, cauterize, and/or seal tissue.

During an electrosurgical procedure, tissue sealing plates are used toapply electrosurgical energy to tissue. Because the sealing platesconduct electricity, care must be taken to electrically insulate thesealing plates from other electrically conductive components of theelectrosurgical forceps and to limit and/or reduce many of the knownundesirable effects related to tissue sealing, e.g., flashover, thermalspread, and stray current dissipation. Typically, tissue sealingsurfaces are disposed on inner facing surfaces of opposing jaw memberssuch that the tissue sealing surfaces are utilized to seal tissuegrasped between the jaw members. Often, the manufacturing of jaw membersrequires the use of a two-shot molding process that includes a pre-shotovermold of insulative material (e.g., plastic) placed between theunderside of the sealing plate and the steel structural support base ofthe jaw member to provide electrical insulation between the jaw memberand the tissue sealing surface.

In the past, significant efforts have been directed to improvements inelectrosurgical instruments and the like, with a view towards providingimproved transmission of electrical energy to patient tissue in both aneffective manner and to reduce the sticking of soft tissue to theinstrument's surface during application. In general, such efforts haveenvisioned non-stick surface coatings, such as polymeric materials, e.g.polytetrafluoroethylene (PTFE, commonly sold under the trademarkTEFLON®) for increasing the lubricity of the tool surface. However,these materials may interfere with the efficacy and efficiency ofhemostasis and have a tendency to release from the instrument'ssubstrate due to formation of microporosity, delamination, and/orabrasive wear, thus exposing underlying portions of the instrument todirect tissue contact and related sticking issues. In turn, these holesor voids in the coating lead to nonuniform variations in the capacitivetransmission of the electrical energy to the tissue of the patient andmay create localized excess heating, resulting in tissue damage,undesired irregular sticking of tissue to the electrodes and furtherdegradation of the non-stick coating.

SUMMARY

In an aspect of the present disclosure, an electrosurgical instrument isprovided. The electrosurgical instrument includes a handle having ashaft that extends therefrom, an end effector disposed at a distal endof the shaft, at least one electrode operably coupled to the endeffector and adapted to couple to a source of electrosurgical energy, atitanium nitride coating covering at least a portion of the electrode, achromium nitride coating covering at least a portion of the electrode,and a hexamethyldisiloxane plasma coating covering at least a portion ofthe chromium nitride coating. The chromium nitride coating may bedisposed over a portion of the titanium nitride coating or all of thetitanium nitride coating. The end effector may include a pair ofopposing jaw members. At least one of the jaw members may include asupport base and an electrical jaw lead, with the electrode coupled tothe electrical jaw lead and the support base. The electrode may includea stainless steel layer and a hexamethyldisiloxane plasma coating may bedisposed over at least a portion of the stainless steel layer.

An electrically insulative layer may be bonded to an underside of thesealing plate. The electrically insulative layer may be formed from apolyimide, a polycarbonate, a polyethylene, and/or any combinationsthereof. In aspects, a titanium nitride coating is disposed on a topsideof the stainless steel layer of the sealing plate, a chromium nitridecoating is disposed over the titanium nitride coating, and thehexamethyldisiloxane plasma coating is disposed over the chromiumnitride coating. The chromium nitride coating may be disposed over aportion of the titanium nitride coating or all of the titanium nitridecoating. The end effector may additionally include an insulative housingdisposed around the support base. A hexamethyldisiloxane plasma coatingmay also be disposed on the sealing plate and the insulative housing.

In another aspect of the present disclosure, an end effector for usewith an electrosurgical instrument for sealing tissue is provided. Theend effector may include a pair of opposing jaw members. At least one ofthe jaw members includes a support base, an electrical jaw lead, asealing plate coupled to the electrical jaw lead and the support base,the sealing plate having a stainless steel layer, a titanium nitridecoating disposed over at least a portion of the stainless steel layer, achromium nitride coating disposed over at least a portion of thetitanium nitride coating, and a hexamethyldisiloxane plasma coatingdisposed over at least one of the support base, the sealing plate, orthe chromium nitride coating. The chromium nitride coating may bedisposed over a portion of the titanium nitride coating or all of thetitanium nitride coating.

The end effector may further include an electrically insulative layerdisposed on at least a portion of an underside of the stainless steellayer. The electrically insulative layer may be formed from a polyimide,a polycarbonate, a polyethylene, and/or any combinations thereof. Inaspects, a titanium nitride coating is disposed on a topside of thestainless steel layer of the sealing plate, a chromium nitride coatingis disposed over at least a portion of the titanium nitride coating, andthe hexamethyldisiloxane plasma coating is disposed over the chromiumnitride coating. The end effector may additionally include an insulativehousing disposed around the support base. A hexamethyldisiloxane plasmacoating may also be disposed on the sealing plate and the insulativehousing.

The hexamethyldisiloxane plasma coating may be disposed on each of thesupport base and the chromium nitride coating. Additionally, oralternatively, the end effector may include an insulative housingdisposed around the support base and the hexamethyldisiloxane plasmacoating may be disposed on the sealing plate and the insulative housing.

In another aspect of the present disclosure, a method of manufacturingan end effector assembly for use with an electrosurgical instrument isprovided. The method includes forming a sealing plate, assembling a jawmember by affixing the sealing plate to a support base, and applying ahexamethyldisiloxane plasma coating to at least a portion of theassembled jaw member.

Forming a sealing plate includes stamping at least one sealing platefrom a stainless steel sheet. Assembling the jaw member may furtherinclude bonding an electrically insulative layer to an underside of thesealing plate and/or overmolding an insulative material about thesupport base to secure the sealing plate thereto. The method may furtherinclude coupling an electrical lead to the sealing plate, the electricallead configured to connect the sealing plate to an energy source.Additionally, or alternatively, the method may further include applyinga titanium nitride coating to at least a portion of the assembled jawmember, applying a chromium nitride coating to at least a portion of theassembled jaw member and/or the titanium nitride coating, and applying ahexamethyldisiloxane plasma coating over at least a portion of thechromium nitride coating. Additionally, or alternatively, the method mayfurther include forming a second seal plate, assembling a second jawmember by affixing the second sealing plate to a second support base,applying a hexamethyldisiloxane plasma coating to at least a portion ofthe second assembled jaw member, and assembling the end effectorassembly by coupling the jaw member to the second jaw member.

In another aspect of the present disclosure, a method for manufacturingan electrosurgical instrument is provided. The method includes applyinga titanium nitride coating to at least a portion of an electricallyconductive surface, applying a chromium nitride coating to at least aportion of the titanium nitride coating, assembling the coatedelectrically conductive surface to a treatment member, and applying ahexamethyldisiloxane plasma coating over at least a portion of thetreatment member. The chromium nitride coating may be disposed over aportion of the titanium nitride coating or all of the titanium nitridecoating. Assembling the coated electrically conductive surface to thetreatment member may include providing a support base to support theelectrically conductive surface, and bonding an electrically insulativelayer to an underside of the electrically conductive surface.

The method may further include overmolding an insulative material aboutthe support base to secure the electrically conductive surface thereto.Additionally, or alternatively, the method may further include formingthe electrically conductive surface by stamping the electricallyconductive surface from a sheet of stainless steel. Additionally, oralternatively, the method may further include coupling an electricallead to the electrically conductive surface, the electrical leadconfigured to connect the electrically conductive surface to an energysource.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other aspects, features, and advantages of the presentdisclosure will become more apparent in light of the following detaileddescription when taken in conjunction with the accompanying drawings inwhich:

FIG. 1 is a perspective view of an endoscopic bipolar forceps inaccordance with an aspect of the present disclosure;

FIG. 2 is a perspective view of an open bipolar forceps according to anaspect of the present disclosure;

FIGS. 3A and 3B are exploded views of opposing jaw members according toan aspect of the present disclosure;

FIG. 4A is a front cross sectional view of a sealing plate according toan aspect of the present disclosure;

FIG. 4B is a front cross sectional view of a jaw member according to anaspect of the present disclosure;

FIG. 5 is a flow chart illustrating a method of manufacturing an endeffector assembly for use with an electrosurgical instrument accordingto an aspect of the present disclosure;

FIG. 6 is a flow chart illustrating a method of manufacturing anelectrosurgical instrument according to an aspect of the presentdisclosure;

FIGS. 7A and 7B are exploded views of opposing jaw members according toan aspect of the present disclosure;

FIG. 8A is a front cross sectional view of a sealing plate according toan aspect of the present disclosure;

FIG. 8B is a front cross sectional view of a jaw member according to anaspect of the present disclosure;

FIG. 9 is a flow chart illustrating a method of manufacturing an endeffector assembly for use with an electrosurgical instrument accordingto an aspect of the present disclosure; and

FIG. 10 is a flow chart illustrating a method of manufacturing anelectrosurgical instrument according to an aspect of the presentdisclosure.

DETAILED DESCRIPTION

Particular aspects of the present disclosure are described hereinbelowwith reference to the accompanying drawings; however, it is to beunderstood that the disclosed aspects are merely examples of thedisclosure and may be embodied in various forms. Well-known functions orconstructions are not described in detail to avoid obscuring the presentdisclosure in unnecessary detail. Therefore, specific structural andfunctional details disclosed herein are not to be interpreted aslimiting, but merely as a basis for the claims and as a representativebasis for teaching one skilled in the art to variously employ thepresent disclosure in virtually any appropriately detailed structure.

Like reference numerals may refer to similar or identical elementsthroughout the description of the figures. As shown in the drawings anddescribed throughout the following description, as is traditional whenreferring to relative positioning on a surgical instrument, the term“proximal” refers to the end of the apparatus which is closer to theuser and the term “distal” refers to the end of the apparatus which isfurther away from the user. The term “clinician” refers to any medicalprofessional (i.e., doctor, surgeon, nurse, or the like) performing amedical procedure involving the use of aspects described herein.

As described in more detail below with reference to the accompanyingfigures, the present disclosure is directed to electrosurgicalinstruments having a hexamethyldisiloxane (“HMDSO”) plasma coatingdisposed on at least a portion thereof. The HMDSO plasma coating may bederived from HMDSO feed stock in plasma. For example, and withoutlimitation, if pure argon is the media for the plasma and HMDSO is thefeedstock, then the HMDSO plasma coating is polymeric with a structureclose to [(CH3)2-Si-O]n. With increasing air content, a gradual changemay be caused from organic polydimethylsiloxane-like coatings toinorganic, quartz-like deposits. For simplicity, the coating will bedescribed herein as a HMDSO plasma coating. As described in furtherdetail below, the coating may be further modified by introduction ofother gasses or feedstocks.

In one aspect, the present disclosure is directed to opposing jawmembers of a vessel sealer instrument having sealing plates with a HMDSOplasma coating deposited over a chromium nitride (“CrN”) coating. Havinga non-stick HMDSO plasma coating disposed on an outer surface of thesealing plate, jaw member, end effector, and/or any other portion of asurgical instrument has many advantages. For instance, HMDSO plasmacoating, used in conjunction with CrN coating, operates to reduce thepitting of sealing plates as is common with arcing. The double coatingprovides durability against electrical and/or mechanical degradation ofthe sealing plates and the jaw members, as a whole, needed for long-terminstrument durability. In particular, the additional HMDSO plasmacoating reduces the sticking of tissue to the jaws or the surroundinginsulating material of the end effector assembly and/or surgicalinstrument.

Another advantage of utilizing the HMDSO plasma coating, in conjunctionwith a CrN coating, is that the HMDSO plasma coating may be applied sothin as to have no functional effect on any tissue sealing properties.Specifically, the HMDSO plasma coating need not have any insulativeeffects. In one example, the resulting coating using HMDSO as afeedstock in the plasma is silicone oxide matrix with a functionalizedsurface, in some instances that of surfaced with —CH3.

Turning now to FIG. 1, an instrument generally identified as forceps 10is for use with various surgical procedures and includes a housing 20, ahandle assembly 30, a rotating assembly 80, a trigger assembly 70, andan end effector assembly 130 that mutually cooperate to grasp, seal, anddivide tubular vessels and vascular tissues. Forceps 10 includes a shaft12 extending from a distal end of the housing 20. The shaft 12 has adistal end 16 dimensioned to mechanically engage the end effectorassembly 130 and a proximal end 14 that mechanically engages the housing20.

The end effector assembly 130 includes opposing jaw members 110 and 120,which cooperate to effectively grasp tissue for sealing purposes. Bothjaw members 110 and 120 pivot relative to one another about a pivot pin(not shown). Alternatively, jaw member 110 may be movable relative to astationary jaw member 120, and vice versa. The jaw members 110 and 120may be curved to facilitate manipulation of tissue and to provide better“line-of-sight” for accessing targeted tissues.

Examples of forceps are shown and described in commonly-owned U.S.application Ser. No. 10/369,894 entitled “VESSEL SEALER AND DIVIDER ANDMETHOD MANUFACTURING SAME” (U.S. Patent Publication No. 2003/0229344)and commonly-owned U.S. application Ser. No. 10/460,926 (now U.S. Pat.No. 7,156,846) entitled “VESSEL SEALER AND DIVIDER FOR USE WITH SMALLTROCARS AND CANNULAS,” the entire contents of each of which areincorporated by reference herein.

With regard to FIG. 2, an open forceps 200 for use with various surgicalprocedures is shown. Forceps 200 includes a pair of opposing shafts 212a and 212 b having an end effector assembly 230 attached to the distalends 216 a and 216 b thereof, respectively. End effector assembly 230includes pair of opposing jaw members 210 and 220 that are pivotablyconnected about a pivot pin 265 and that are movable relative to oneanother to grasp tissue. Each shaft 212 a and 212 b includes a handle215 and 217, respectively, disposed at the proximal end 214 a and 214 bthereof and that each define a finger hole 215 a and 217 a,respectively, therethrough for receiving a finger of the user. Fingerholes 215 a and 217 a facilitate movement of the shafts 212 a and 212 brelative to one another to pivot the jaw members 210 and 220 between anopen position, wherein the jaw members 210 and 220 are disposed inspaced relation relative to one another, and a clamping or closedposition, wherein the jaw members 210 and 220 cooperate to grasp tissuetherebetween.

FIGS. 3A and 3B are perspective views of opposing jaw members 310 and320 according to one aspect of the present disclosure which may beutilized with both endoscopic forceps 10 (FIG. 1) and open forceps 200(FIG. 2). Similar to jaw members 110 and 120 (FIG. 1) and jaw members210 and 220 (FIG. 2), each of the jaw members 310 and 320 include:sealing plates 312 and 322 (also referred to herein as electricallyconductive plate, conductive plates, and/or electrodes), respectively;electrical jaw leads 325 a and 325 b, respectively; and support bases319 and 329 that extend distally from flanges 313 and 323, respectively.

Each of sealing plates 312 and 322 include an underside 328 a and 328 b,respectively, that may include a respective electrically insulativelayer 330 a and 330 b bonded thereto or otherwise disposed thereon.Electrically insulative layers 330 a and 330 b operate to electricallyinsulate sealing plates 312 and 322, respectively, from support bases319 and 329, respectively. Further, electrically insulative layers 330 aand 330 b operate to prevent or slow the onset of corrosion of sealingplates 312 and 322, respectively, at least on the undersides 328 a, 328b thereof. In one embodiment, electrically insulative layers 330 a and330 b may be formed from polyimide. However, in other embodiments, anysuitable electrically insulative material may be utilized, such aspolycarbonate, polyethylene, etc.

Additionally, each of jaw members 310 and 320 include an outer surface311 a and 311 b, respectively, that may include a respective chromiumnitride (“CrN”) coating 400 a and/or hexamethyldisiloxane (“HMDSO”)plasma coating 400 b disposed, or otherwise deposited, thereon. CrNcoating 400 a and/or HMDSO plasma coating 400 b may be disposed onselective portions of either of jaw member 310 and 320, or may bedisposed on the entire outer surfaces 311 a and 311 b. In oneembodiment, CrN coating 400 a and HMDSO plasma coating 400 b is disposedon an outer surface 317 a and/or 317 b of sealing plates 312 and 322,respectively. HMDSO plasma coating 400 b, used in conjunction with CrNcoating 400 a, operates to reduce the pitting of sealing plates 312 and322 as is common with arcing. The double coating provides durabilityagainst electrical and/or mechanical degradation of the sealing plates312 and 322 and the jaw members 310 and 320 as a whole, needed forlong-term instrument durability. In particular, the additional HMDSOplasma coating 400 b reduces the sticking of tissue to the jaw members310 and 320 or the surrounding insulating material.

Support bases 319 and 329 are configured to support electricallyconductive sealing plates 312 and 322 thereon. Sealing plates 312 and322 may be affixed atop the support bases 319 and 329, respectively, byany suitable method including but not limited to snap-fitting,overmolding, stamping, ultrasonic welding, etc. The support bases 319and 329 and sealing plates 312 and 322 are at least partiallyencapsulated by insulative housings 316 and 326, respectively, by way ofan overmolding process to secure sealing plates 312 and 322 to supportbases 319 and 329, respectively. The sealing plates 312 and 322 arecoupled to electrical jaw leads 325 a and 325 b, respectively, via anysuitable method (e.g., ultrasonic welding, crimping, soldering, etc.).Electrical jaw lead 325 a supplies a first electrical potential tosealing plate 312 and electrical jaw lead 325 b supplies a secondelectrical potential to opposing sealing plate 322.

Jaw member 320 (and/or jaw member 310) may also include a series of stopmembers 390 disposed on the topside surface 317 a (the inner facingsurface) of sealing plate 312 to facilitate gripping and manipulation oftissue and to define a gap between opposing jaw members 310 and 320during sealing and cutting of tissue. The series of stop members 390 areapplied onto the sealing plate 312 during manufacturing. Some or all ofthe stop members 390 may be coated with the CrN coating 400 a and/or theHMDSO plasma coating 400 b, or alternatively may be disposed on top ofthe CrN coating 400 a and/or the HMDSO plasma coating 400 b. Further,the sealing plates 312 and 322 may include longitudinally-oriented knifeslots 315 a and 315 b, respectively, defined therethrough forreciprocation of a knife blade (not shown). The electrically insulativelayers 330 a and 330 b disposed on the undersides 328 a and 328 b,respectively, of sealing plates 312 and 322, respectively, allow forvarious blade configurations such as, for example, T-shaped blades orI-shaped blades that may contact the underside of the sealing plate(and/or insulating layer) during reciprocation through knife slots 315a, 315 b. That is, the electrically insulative layers 330 a, 330 boperate to protect both the knife blade and the undersides 328 a and 328b of the sealing plates 312 and 322, respectively, from damage orwearing. Further, in the instance that an electrically conductive knifeblade is utilized (e.g., for electric tissue cutting), the electricallyinsulative layers 330 a, 330 b help to electrically insulate the sealingplates 312, 322 from the electrically conductive knife blade.

Turning now to FIG. 4A, a front cross sectional view of sealing plate312 is shown and will be described. Sealing plate 312 has a stainlesssteel layer 317, an electrically insulative layer 330 a, a CrN coating400 a, and an HMDSO plasma coating 400 b. Sealing plate 312 may beformed by bonding electrically insulative layer 330 a to the underside328 b of stainless steel layer 317, coating at least the upper surface317 a of the stainless steel layer 317 with a CrN coating 400 a, andcoating at least a portion of the CrN coating 400 a and/or the stainlesssteel layer 317 with an HMDSO plasma coating 400 b. Bonding electricallyinsulative layer 330 a to stainless steel layer 317 may be accomplishedby any suitable method including, but not limited to, applying adhesivebetween electrically insulative layer 330 a and stainless steel layer317, using heat treatment to bond electrically insulative layer 330 a tostainless steel layer 317, and/or any combinations thereof. Electricallyinsulative layer 430 a may have a thickness ranging from about 0.001inches to about 0.005 inches. Sealing plate 312, which includesstainless steel layer 317, electrically insulative layer 330 a, CrNcoating 400 a and HMDSO plasma coating 400 b, may have a thicknessranging from about 0.005 inches to about 0.010 inches.

Sealing plate 312 may be formed by bonding a sheet of electricallyinsulative to a sheet of stainless steel and coating the sheet ofstainless steel with at least one of a CrN coating and/or an HMDSOplasma coating. Once the two materials are bonded together, and thestainless steel sheet is coated with one or both of the CrN layer and/orthe HMDSO plasma layer, sealing plate 312 may be formed by stamping,machining, or any other suitable method used to form a sealing plate.

Turning now to FIG. 4B, a front cross sectional view of jaw member 310is shown and will be described. Jaw member 310 includes sealing plate312 having a stainless steel layer 317 and, optionally, an electricallyinsulative layer 330 a. Sealing plate 312 is affixed to support base 319via any suitable process. Additionally, with sealing plate 312 securedto support base 319, the combined sealing plate 312 and support base 319is secured to insulative housing 316 via any suitable process. A CrNcoating 400 a is disposed over the outer surface 311 a of the assembledsealing plate 312, support base 319, and insulative housing 316.Additionally, an HMDSO plasma coating 400 b is disposed over the CrNcoating 400 a. As described above, in embodiments it may be useful tocoat only a partial outer surface 311 a of the jaw member 310 or includethicker layers of the CrN coating 400 a and/or the HMDSO plasma coating400 b on different portions of the outer surface 311 a of the jaw member310.

Additionally, or alternatively, in embodiments, the sealing plates 312may be coated in the manner described above with respect to FIG. 4A andthe outer surface 311 a of the jaw member 310 may also be coated withthe CrN coating 400 a and/or the HMDSO plasma coating 400 b.

Turning now to FIG. 5, a method for manufacturing an HMDSO plasma coatedend effector assembly is illustrated and will be described as method500. Method 500 begins in step 501 where a CrN coating and/or an HMDSOplasma coating is applied to a sealing plate.

The HMDSO plasma coating may be applied using a system or process whichincludes a plasma device that is coupled to a power source, an ionizablemedia source and a precursor or pre-ionization source similar to thesystem described in U.S. Patent Publication No. 2013/0116682, filed onNov. 9, 2011, the contents of which is incorporated by reference hereinin its entirety. The power source may include any suitable componentsfor delivering power or matching impedance to the plasma device. Moreparticularly, the power source may be any radio frequency generator orother suitable power source capable of producing electrical power toignite and sustain the ionizable media to generate a plasma effluent.

Plasmas are generated using electrical energy that is delivered aseither direct current (DC) electricity or alternating current (AC)electricity, in either continuous or pulsed modes, at frequencies fromabout 0.1 hertz (Hz) to about 100 gigahertz (GHz), including radiofrequency bands (“RF”, from about 0.1 MHz to about 100 MHz) andmicrowave bands (“MW”, from about 0.1 GHz to about 100 GHz), usingappropriate generators, electrodes, and antennas. AC electrical energymay be supplied at a frequency from about 0.1 MHz to about 2,450 MHz, inembodiments from about 1 MHz to about 160 MHz. The plasma may also beignited by using continuous or pulsed direct current (DC) electricalenergy or continuous or pulsed RF electrical energy or combinationsthereof. Choice of excitation frequency, the workpiece, as well as theelectrical circuit that is used to deliver electrical energy to thecircuit affects many properties and requirements of the plasma. Theperformance of the plasma chemical generation, the gas or liquidfeedstock delivery system and the design of the electrical excitationcircuitry are interrelated, as the choices of operating voltage,frequency and current levels, as well as phase, effect the electrontemperature and electron density. Further, choices of electricalexcitation and plasma device hardware also determine how a given plasmasystem responds dynamically to the introduction of new ingredients tothe host plasma gas or liquid media. The corresponding dynamicadjustment of the electrical drive, such as via dynamic match networksor adjustments to voltage, current, or excitation frequency may be usedto maintain controlled power transfer from the electrical circuit to theplasma.

Continuing with reference to FIG. 5, the sealing plate may be formed ofstainless steel which is stamped from a large stainless steel sheetwhich has already been coated with any of the coatings described herein.Method 500 may optionally also include step 503 where an insulativelayer is bonded or otherwise affixed to an underside of the sealingplate. In some aspects, the insulative layer may be bonded to an entiresheet of stainless steel and the sealing plate is stamped from the sheetof stainless steel after the insulative layer is bonded to the sheet ofstainless steel.

In step 505, the jaw member is assembled. Specifically, in step 505 thecoated sealing plate is affixed to a support base and/or an insulativehousing. In 505, the jaw member may be assembled via any suitableprocess including insert molding. In step 507, an HMDSO plasma coatingis applied to at least a portion of the assembled jaw member. Step 507may be carried out via plasma coating. The HMDSO plasma coating may beenhanced by the addition of oxygen or fluorine in the plasma anddeposition. Any or all of steps 501-507, described above, are repeatedto assemble an opposing (second) jaw member. In step 509, the firstassembled jaw member and the second assembled jaw member are assembledto form a coated end effector assembly. That is, the first assembled jawmember is pivotably coupled to the second assembled jaw member to createthe assembled coated end effector assembly.

Turning now to FIG. 6, a method for manufacturing an HMDSO plasma coatedend instrument is illustrated and will be described as method 600.Method 600 begins in step 601 where a CrN coating is applied to at leasta portion of an electrically conductive surface. The electricallyconductive surface may be a sealing plate which may be formed ofstainless steel. The stainless steel may be stamped from a largestainless steel sheet which has already been coated with any of thecoatings described herein. Method 600 may optionally also include a stepwhere an insulative layer is bonded or otherwise affixed to an undersideof the electrically conductive surface. In some aspects, the insulativelayer may be bonded to an entire sheet of stainless steel and theelectrically conductive surface is stamped from the sheet of stainlesssteel after the insulative layer is bonded to the sheet of stainlesssteel.

In step 603, a treatment member is assembled. The treatment member maybe a jaw member as previously described herein. Specifically, in step603 the coated electrically conductive surface is affixed to a supportbase and/or an insulative housing. In 603, the treatment member may beassembled via any suitable process including insert molding. In step605, an HMDSO plasma coating is applied to at least a portion of theelectrically conductive surface and/or the assembled treatment member.Step 605 may be carried out via plasma coating the electricallyconductive surface and/or the assembled treatment member. The HMDSOplasma coating may be enhanced by the addition of oxygen or fluorine inthe plasma and deposition. Any or all of steps 601-605, described above,may be repeated to assemble an opposing (second) treatment member.

As described in more detail below with reference to the accompanyingfigures, another aspect of the present disclosure is directed toelectrosurgical instruments having a HMDSO plasma coating disposed on atleast a portion thereof, in combination with a portion of the instrumentbeing coated with CrN and a portion of the instrument being coated withtitanium nitride (“TiN”). As described above, the HMDSO plasma coatingmay be derived from HMDSO feed stock in plasma. For example, and withoutlimitation, if pure argon is the media for the plasma and HMDSO is thefeedstock, then the HMDSO plasma coating is polymeric with a structureclose to [(CH3)2-Si-O]n. With increasing air content, a gradual changemay be caused from organic polydimethylsiloxane-like coatings toinorganic, quartz-like deposits. For simplicity, the coating will bedescribed herein as a HMDSO plasma coating. As described in furtherdetail below, the coating may be further modified by introduction ofother gasses or feedstocks.

In one aspect, the present disclosure is directed to opposing jawmembers of a vessel sealer instrument having sealing plates with a HMDSOplasma coating deposited over at least a portion of CrN coating, and theCrN coating deposited over at least a portion of a TiN coating. Having anon-stick HMDSO plasma coating disposed on an outer surface of thesealing plate, jaw member, end effector, and/or any other portion of asurgical instrument has many advantages. For instance, HMDSO plasmacoating, used in conjunction with CrN coating and TiN coating operatesto reduce the pitting of sealing plates as is common withelectrosurgical arcing. The multiple layered coating provides durabilityagainst electrical and/or mechanical degradation of the sealing platesand the jaw members, as a whole, needed for long-term instrumentdurability. In particular, the additional HMDSO plasma coating incombination with a TiN and CrN coating reduces the sticking of tissue tothe jaws or the surrounding insulating material of the end effectorassembly and/or surgical instrument.

Turning now to FIGS. 8A-8B, aspects of an electrosurgical instrumentincluding a multi-layered coating comprising any of HMDSO, CrN, or TiNwill be described. Each of jaw members 310 and 320 includes an outersurface 311 a and 311 b, respectively, that may include a respective TiNcoating 400 c, CrN coating 400 a, and/or HMDSO plasma coating 400 bdisposed, or otherwise deposited, thereon. TiN coating 400 c, CrNcoating 400 a, and/or HMDSO plasma coating 400 b may be disposed onselective portions of either or both jaw members 310 and 320, or may bedisposed on the entire outer surfaces 311 a and 311 b. In oneembodiment, TiN coating 400 c, CrN coating 400 a, and HMDSO plasmacoating 400 b is disposed on an outer surface 317 a and/or 317 b ofsealing plates 312 and 322, respectively. As mentioned above, HMDSOplasma coating 400 b, used in conjunction with CrN coating 400 a and TiNcoating 400 c, operates to reduce the pitting of sealing plates 312 and322 as is common with arcing. The triple coating provides durabilityagainst electrical and/or mechanical degradation of the sealing plates312 and 322 and the jaw members 310 and 320 as a whole, which improveslong-term instrument durability. In particular, the additional HMDSOplasma coating 400 b over the CrN coating 400 a and the TiN coating 400c reduces the sticking of tissue to the jaw members 310 and 320 or thesurrounding insulating material.

Support bases 319 and 329 are configured to support electricallyconductive sealing plates 312 and 322 thereon. Sealing plates 312 and322 may be affixed atop the support bases 319 and 329, respectively, byany suitable method including but not limited to snap-fitting,overmolding, stamping, ultrasonic welding, etc. The support bases 319and 329 and sealing plates 312 and 322 are at least partiallyencapsulated by insulative housings 316 and 326, respectively, by way ofan overmolding process to secure sealing plates 312 and 322 to supportbases 319 and 329, respectively. The sealing plates 312 and 322 arecoupled to electrical jaw leads 325 a and 325 b, respectively, via anysuitable method (e.g., ultrasonic welding, crimping, soldering, etc.).Electrical jaw lead 325 a supplies a first electrical potential tosealing plate 312 and electrical jaw lead 325 b supplies a secondelectrical potential to opposing sealing plate 322.

Jaw member 320 (and/or jaw member 310) may also include a series of stopmembers 390 disposed on the inner facing surface 317 a of sealing plate312 to facilitate gripping and manipulation of tissue and to define agap between opposing jaw members 310 and 320 during sealing and cuttingof tissue. The series of stop members 390 are applied onto the sealingplate 312 during manufacturing. Some or all of the stop members 390 maybe coated with the TiN coating 400 c, CrN coating 400 a, and/or theHMDSO plasma coating 400 b, or alternatively may be disposed on top ofthe TiN coating 400 c, CrN coating 400 a, and/or the HMDSO plasmacoating 400 b. Further, the sealing plates 312 and 322 may includelongitudinally-oriented knife slots 315 a and 315 b, respectively,defined therethrough for reciprocation of a knife blade (not shown). Theelectrically insulative layers 330 a and 330 b disposed on theundersides 328 a and 328 b, respectively, of sealing plates 312 and 322,respectively, allow for various blade configurations such as, forexample, T-shaped blades or I-shaped blades that may contact theunderside of the sealing plate (and/or insulating layer) duringreciprocation through knife slots 315 a, 315 b. That is, theelectrically insulative layers 330 a, 330 b operate to protect both theknife blade and the undersides 328 a and 328 b of the sealing plates 312and 322, respectively, from damage or wearing. Further, in the instancethat an electrically conductive knife blade is utilized (e.g., forelectric tissue cutting), the electrically insulative layers 330 a, 330b help to electrically insulate the sealing plates 312, 322 from theelectrically conductive knife blade.

Turning now to FIG. 7A, a front cross sectional view of sealing plate312 is shown and will be described. Sealing plate 312 has a stainlesssteel layer 317, an electrically insulative layer 330 a, a TiN coating400 c, a CrN coating 400 a, and an HMDSO plasma coating 400 b. Sealingplate 312 may be formed by bonding electrically insulative layer 330 ato the underside 328 b of stainless steel layer 317, coating at leastthe upper surface 317 a of the stainless steel layer 317 with a TiNcoating 400 c, coating at least a portion of the TiN coating 400 cand/or the stainless steel layer 317 with a CrN coating 400 a, andcoating at least a portion of the CrN coating 400 a and/or the stainlesssteel layer 317 with an HMDSO plasma coating 400 b. Bonding electricallyinsulative layer 330 a to stainless steel layer 317 may be accomplishedby any suitable method including, but not limited to, applying adhesivebetween electrically insulative layer 330 a and stainless steel layer317, using heat treatment to bond electrically insulative layer 330 a tostainless steel layer 317, and/or any combinations thereof. Electricallyinsulative layer 430 a may have a thickness ranging from about 0.001inches to about 0.005 inches. Sealing plate 312, which includesstainless steel layer 317, electrically insulative layer 330 a, TiNcoating 400 c, CrN coating 400 a, and HMDSO plasma coating 400 b, mayhave a thickness ranging from about 0.005 inches to about 0.010 inches.

Sealing plate 312 may be formed by bonding a sheet of electricallyinsulative material to a sheet of stainless steel and coating the sheetof stainless steel with at least one of a TiN coating, a CrN coating,and/or an HMDSO plasma coating. Once the materials are bonded together,and the stainless steel sheet is coated with one, two, or all three ofthe TiN layer, the CrN layer, and/or the HMDSO plasma layer, sealingplate 312 may be formed by stamping, machining, or any other suitablemethod used to form a sealing plate.

Turning now to FIG. 8B, a front cross sectional view of jaw member 310is shown and will be described. Jaw member 310 includes sealing plate312 having a stainless steel layer 317 and, optionally, an electricallyinsulative layer 330 a. Sealing plate 312 is affixed to support base 319via any suitable process. Additionally, with sealing plate 312 securedto support base 319, the combined sealing plate 312 and support base 319is secured to insulative housing 316 via any suitable process. A TiNcoating 400 c and/or a CrN coating 400 a is disposed over the outersurface 311 a of the assembled sealing plate 312, support base 319, andinsulative housing 316. In one aspect, the TiN coating 400 c is disposedover the stainless steel layer 317 and the CrN coating 400 a is disposedover the outer surface 311 a of the assembled sealing plate 312(including the TiN coating 400 c), support base 319, and insulativehousing 316. In another aspect, the TiN coating 400 c is disposed overthe outer surface 311 a of the assembled sealing plate 312, support base319, and insulative housing 316 and the CrN coating 400 a is disposedover a portion of, or all of, the TiN coating 400 c. Additionally, anHMDSO plasma coating 400 b is disposed over the CrN coating 400 a. Asdescribed above, in embodiments it may be useful to coat only a partialouter surface 311 a of the jaw member 310 or include thicker layers ofthe TiN coating 400 c, CrN coating 400 a, and/or the HMDSO plasmacoating 400 b on different portions of the outer surface 311 a of thejaw member 310.

Additionally, or alternatively, in embodiments, the sealing plates 312may be coated in the manner described above with respect to FIG. 8A andthe outer surface 311 a of the jaw member 310 may also be coated withthe TiN coating 400 c, CrN coating 400 a, and/or the HMDSO plasmacoating 400 b.

Turning now to FIG. 9, a method for manufacturing an HMDSO plasma coatedend effector assembly is illustrated and will be described as method900. Method 900 begins in step 901 where a TiN coating is applied to asealing plate (for example, a stainless steel layer). Subsequent tocoating the sealing plate with TiN (step 901), in step 903 a CrN coatingand/or an HMDSO plasma coating is applied to a sealing plate over theTiN coating. Step 903 may include coating the entire TiN layer with CrN,or coating only a portion of the TiN layer with CrN. Additionally, step903 may include depositing a CrN coating over portions of the sealingplate that have not been coated with TiN.

Method 900 may optionally also include step 905 where an insulativelayer is bonded or otherwise affixed to an underside of the sealingplate. In some aspects, the insulative layer may be bonded to an entiresheet of stainless steel and the sealing plate is stamped from the sheetof stainless steel after the insulative layer is bonded to the sheet ofstainless steel.

In step 907, the jaw member is assembled. Specifically, in step 907 thecoated sealing plate is affixed to a support base and/or an insulativehousing. In 907, the jaw member may be assembled via any suitableprocess including insert molding. In step 909, an HMDSO plasma coatingis applied to at least a portion of the assembled jaw member. Step 909may be carried out via plasma coating in accordance with the methodsdescribed above. The HMDSO plasma coating may be enhanced by theaddition of oxygen or fluorine in the plasma and deposition. Any or allof steps 901-909, described above, are repeated to assemble an opposing(second) jaw member. In step 911, the first assembled jaw member and thesecond assembled jaw member are assembled to form a coated end effectorassembly. That is, the first assembled jaw member is pivotably coupledto the second assembled jaw member to create the assembled coated endeffector assembly.

Turning now to FIG. 10, a method for manufacturing an HMDSO plasmacoated end instrument is illustrated and will be described as method1000. Method 1000 begins in step 1001 where a TiN coating is applied toat least a portion of an electrically conductive surface. Theelectrically conductive surface may be a sealing plate which may beformed of stainless steel. The stainless steel may be stamped from alarge stainless steel sheet which has already been coated with any ofthe coatings described herein. Method 1000 may optionally also include astep where an insulative layer is bonded or otherwise affixed to anunderside of the electrically conductive surface. In some aspects, theinsulative layer may be bonded to an entire sheet of stainless steel andthe electrically conductive surface is stamped from the sheet ofstainless steel after the insulative layer is bonded to the sheet ofstainless steel.

In step 1003, a CrN coating is applied over the TiN coating. Asdescribed above, step 1003 may include applying the CrN coating overportions of the electrically conductive surface that are not coated withthe TiN coating. Alternatively, step 1003 may include applying the CrNcoating over the entire TiN coating.

In step 1005, a treatment member is assembled. The treatment member maybe a jaw member as previously described herein. Specifically, in step1005 the coated electrically conductive surface is affixed to a supportbase and/or an insulative housing. In 1005, the treatment member may beassembled via any suitable process including insert molding. In step1007, an HMDSO plasma coating is applied to at least a portion of theelectrically conductive surface and/or the assembled treatment member.Step 1007 may be carried out via plasma coating the electricallyconductive surface and/or the assembled treatment member. The HMDSOplasma coating may be enhanced by the addition of oxygen or fluorine inthe plasma and deposition. Any or all of steps 1001-1007, describedabove, may be repeated to assemble the opposing (second) treatmentmember.

Although the above-described aspects are directed to CrN, TiN, and HMDSOcoatings, it is appreciated that any nitride physical vapor depositioncoating may be utilized in place of the CrN coating and/or the TiNcoating. For example, other coatings that may be used in place of theCrN coating and/or the TiN coating may include TiAlCN, TiZrN, CrAlN,CrAlCN, AlCrN, multilayer designs, nanolayered coatings, nanocompositecoatings, diamond-like coatings, or any combinations thereof.Additionally, although FIGS. 8A, 8B, 9, and 10 are described asincluding a CrN coating over a TiN coating, it is appreciated that theTiN coating may be replaced with a CrN coating or any other coating.

It should be understood that the foregoing description is onlyillustrative of the present disclosure. Various alternatives andmodifications can be devised by those skilled in the art withoutdeparting from the disclosure. Accordingly, the present disclosure isintended to embrace all such alternatives, modifications and variances.The embodiments described with reference to the attached drawings arepresented only to demonstrate certain examples of the disclosure. Otherelements, steps, methods and techniques that are insubstantiallydifferent from those described above and/or in the appended claims arealso intended to be within the scope of the disclosure.

1. (canceled)
 2. A surgical instrument, comprising: a shaft; an endeffector disposed adjacent a distal end of the shaft, the end effectorincluding at least one sealing plate; a chromium nitride coatingcovering at least a portion of the at least one sealing plate; atitanium nitride coating covering at least a portion of the at least onesealing plate; and a hexamethyldisiloxane plasma coating covering atleast a portion of the chromium nitride coating or the titanium nitridecoating of the at least one sealing plate.
 3. The surgical instrumentaccording to claim 2, wherein the end effector includes a pair ofopposing jaw members, at least one of the jaw members including anelectrical jaw lead, the at least one sealing plate coupled to theelectrical jaw lead.
 4. The surgical instrument according to claim 2,wherein at least a portion of the at least one sealing plate is formedof stainless steel and wherein the hexamethyldisiloxane plasma coatingis disposed over at least a portion of the stainless steel.
 5. Thesurgical instrument according to claim 4, further comprising anelectrically insulative layer disposed on at least a portion of anunderside of the stainless steel of the at least one sealing plate. 6.The surgical instrument according to claim 5, wherein the electricallyinsulative layer is formed from a material selected from the groupconsisting of a polyimide, polycarbonate, and polyethylene.
 7. Thesurgical instrument according to claim 2, wherein the chromium nitridecoating or the titanium nitride coating covers at least a portion of theat least one sealing plate at varying thicknesses along a lengththereof.
 8. An end effector assembly, comprising: a jaw member; achromium nitride coating disposed on at least a portion of the jawmember; a titanium nitride coating disposed on at least a portion of thejaw member; and a hexamethyldisiloxane plasma coating disposed on atleast a portion of the chromium nitride coating or at least a portion ofthe titanium nitride coating.
 9. The end effector assembly according toclaim 8, wherein the jaw member includes a stainless steel layer. 10.The end effector assembly according to claim 9, wherein the chromiumnitride coating or the titanium nitride coating is disposed on at leasta portion of the stainless steel layer.
 11. The end effector assemblyaccording to claim 9, further comprising an electrically insulativelayer disposed on at least a portion of an underside of the stainlesssteel layer.
 12. The end effector assembly according to claim 11,wherein the electrically insulative layer is formed from a materialselected from the group consisting of a polyimide, polycarbonate, andpolyethylene.
 13. The end effector assembly according to claim 9,wherein the jaw member includes a support base and a sealing platecoupled to the support base, and wherein at least a portion of thesealing plate includes the stainless steel layer.
 14. The end effectorassembly according to claim 13, wherein the support base is free fromdirect contact with the stainless steel layer.
 15. The end effectorassembly according to claim 13, wherein the hexamethyldisiloxane plasmacoating is disposed on the support base and the sealing plate.
 16. Theend effector assembly according to claim 8, wherein the jaw memberincludes a support base and an insulative housing disposed around thesupport base, wherein the hexamethyldisiloxane plasma coating isdisposed on the sealing plate and the insulative housing.
 17. A methodof manufacturing a surgical instrument, comprising: applying a chromiumnitride coating to at least a portion of a jaw member of the surgicalinstrument; applying a titanium nitride coating to at least a portion ofa jaw member of the surgical instrument; and applying ahexamethyldisiloxane plasma coating to at least a portion of the jawmember.
 18. The method according to claim 17, wherein thehexamethyldisiloxane plasma coating is applied over at least one of aportion of the chromium nitride coating or a portion of the titaniumnitride coating.
 19. The method according to claim 17, wherein at leastone of the chromium nitride coating or the titanium nitride coating isapplied to an electrically conductive surface of the jaw member.
 20. Themethod according to claim 19, wherein the chromium nitride coating isapplied over the titanium nitride coating.
 21. The method according toclaim 19, further comprising forming the electrically conductive surfaceby stamping the electrically conductive surface from a sheet ofstainless steel.